http://www.kk.org/cooltools/archives/000723.php
Hand held, hammer powered impact tool.
No tool box should be complete with out one. Put a 3/8 drive socket type tool ( socket, allen, torx or what ever ) on the end, select rotation direction, put on bolt and smack w/ a hammer and the stubborn ( pain in the ass ) bolt comes out. Takes mere seconds ( less than a beer anyway ) to remove a frozen bolt / screw. Even breaks loose bolts with loc-tite.
Been using for YEARS and never encountered a bolt ( 3/8ths and smaller ) that would not give it up to this little wonder tool.
Hopes this helps all out there w/ stubborn bolt syndrome.